From Academic Kids
At the most innocuous level, the term is applied to the legal and mundane methods of examining corporate publications, web sites, patent filings, and the like to determine the activities of a corporation (though this is normally referred to as business intelligence), through to illegal methods such as bribery, blackmail, technological surveillance and even occasional violence. As well as spying on commercial organisations, governments can also be targets of commercial espionage - for example, to determine the terms of a tender for a government contract so that another tenderer can underbid.
Most large corporations openly acknowledge the existence of departments to perform the legal aspects of corporate espionage. Many also spend considerable amounts on precautions to protect against the more cloak-and-dagger varieties.
The United States government has admitted to using commercial espionage, for instance using surveillance of phone calls to determine that a French competitor of a US firm was bribing Brazilian officials to obtain an air traffic control radar contract (it was later revealed that the US firm was also bribing officials). It is generally believed that most large intelligence agencies are involved in the practice. A commission of the European Parliament suspects that ECHELON, a communications espionage system operated by the NSA and agencies of the United Kingdom, Canada, Australia and New Zealand, is used for political espionage and occasionally to help American companies against European competitors.
On a more mundane level, millions of computer owners, including some owning iMac G5s or high-end servers, have personally felt the effects of industrial espionage gone wrong through failing electrolytic capacitors crippling their systems -- believed to be caused by either intentional or accidental misinformation being taken as correct by the culprits.
- Recent cases and future of industrial espionage (http://samvak.tripod.com/pp144.html)